1. Field of the Invention
This invention relates to novel catalysts for the polymerization of olefins. More particularly, it is concerned with a process for the polymerization of olefins characterized in that a solid obtained by pulverizing a titanium compound, a component of a Ziegler catalyst, together with a magnesium halide and/or a manganese halide and an organohalide, is used as one component and, in the presence of a catalyst consisting of such solid and an organometallic compound of a metal of Groups I to IV of the Periodic Table, olefin(s) is(are) polymerized or copolymerized, whereby the yield of polymer per solid and that per transition metal are remarkably increased and a polymer having a high bulk density is obtained in high yield, resulting in the step of removing the residual catalyst becoming unnecessary.
2. Description of the Prior Art
Conventionally in the technical field of this sort there have been known, from Japanese Patent Publication No. 12105/1964, a catalyst consisting of a magnesium halide and a transition metal compound such as a titanium compound carried thereon and, from Belgian Pat. No. 742,112, a catalyst obtained by copulverizing a magnesium halide and a titanium tetrachloride.
In the preparation of polyolefins, however, it is desirable in point of productivity and slurry handling that the bulk density of the resulting polymer be as high as possible. From this point of view, with the process disclosed in the foregoing Japanese Patent Publication No. 12105/1964, the bulk density of the resulting polymer is low and the polymerization activity is not satisfactory; and, with the process of Belgian Pat. No. 742,112, the bulk density of the resulting polymer is low although the polymerization activity is high. Thus, improvements have been desired.